"Grounds for the suit seem to be contract provisions...although one would think CBS poured over them before taking decisive action."

CBS lawyers undoubtedly pored over the contract before he was terminated. It does not follow, however, that lawyers advised CBS that it could terminate him without paying him a large amount of money. It most likely just means that CBS decided that in the big picture paying him to not be on the network beats paying him to be on it.

Now, the issues will be about how much money that will be and to what extent Imus can use a mouthpiece to make him appear a victim to some extent to some larger segment of the population at large.